The stuff in synthetic turf that helps make it green needs routine monitoring for lead hazards and guidelines to assess them, a UNLV professor and six colleagues concluded after a recent study.
That's because the "green stuff" in fake grass is lead chromate. When the compound breaks down, it can release lead that could conceivably be inhaled or ingested by those who play on it -- everyone from football players to kids in day care centers and parks.
So far, no one has reported ill effects from any synthetic turf, according to industry experts.
But the turf needs inspection, according to UNLV's Shawn Gerstenberger and researchers in New Jersey, New York and Georgia. They presented their findings in the October issue of the peer-reviewed research journal, Environmental Health Perspectives.
"The big issue is none of the standards apply and we have standards everywhere for lead," said Gerstenberger, an environmental health professor at the University of Nevada, Las Vegas.
The guideline for consumer products intended for use by children limits lead to 300 parts per million, or 0.03 percent, and the Environmental Protection Agency lead-dust hazard is 40 micrograms per square foot for floors. But neither guideline applies specifically to synthetic turf that contains lead chromate to give nylon fibers or nylon blend fibers their green coloring.
"We are very proud of our unblemished record of environmental safety," Rick Doyle, president of a nonprofit trade group, the Synthetic Turf Council, said Monday.
Doyle said his organization is "fully in support of research and data that will support a risk factor." He said he views the team's study as "an opinion that we will look carefully into."
The lead chromate pigments used in turf fibers are encapsulated so they won't dissolve if ingested, he said.
However, some recreational fields and playgrounds that have artificial turf, including several in Las Vegas, have been closed amid concerns that have surfaced that lead in turf fibers may pose a hazard for children who could ingest them or inhale lead-laced dust after fibers break down in the environment.
In their report, the research team noted, "To date, no study has linked turf exposure to elevated childhood blood lead levels. However, physicians should be aware of synthetic turf as one potential source of exposure for young children, especially given its use in residential, child care or other play environments."
Scientists have observed adverse health effects, in addition to problems with learning and behavior, in children with elevated lead levels in their blood, according to the Center for Disease Control and Prevention.
Gerstenberger said adults who participate in athletics or exercise on synthetic turf fields have a much lower risk of exposure than children, who are more prone to have hand-to-mouth contact with turf fibers or tainted dust.
Awareness about the potential environmental health problem was heightened as the researchers set out to collect samples in 2008, the year after a synthetic turf recreational field in Newark, N.J., was shut down when lead was found in turf fibers and surface dust at hazardous levels. The problem with dust containing high levels of lead in that case was linked in part to a nearby scrap metal facility.
Nevertheless, the Centers for Disease Control and Prevention issued an alert in June 2008 to test aging turf fields where nylon fibers or those made of nylon blends were degrading from wear, ultraviolet radiation and extreme temperatures.
Gerstenberger and colleagues Gregory Van Ulirsch, Kevin Gleason, Daphne B. Moffett, Glenn Pulliam, Tariq Ahmed and Jerald Fagliano collected fiber and dust samples from a variety of synthetic turf areas in Nevada, New Jersey, New York and an Army post in South Korea. The samples were sent to certified laboratories for analysis.
Of the 33 synthetic turf fields tested, about half -- 16 fields -- exceeded the EPA and consumer product limits.
In the Las Vegas Valley, five out of seven synthetic turfs at child care facilities exceeded the consumer products lead content guideline. Four of those had 100 percent nylon fibers, and the fifth was made of polyethylene nylon. The names of the facilities sampled were not released to the public.
When the operators were made aware of the results, "they either shut it down, ripped it out or took action so kids wouldn't get exposed," Gerstenberger said.
But he is not suggesting a ban on artificial turf.
"Just because there's lead in something doesn't mean you're going to get exposed," he said.
What's important, he said, is to test those surfaces with lead content every year to ensure they are not releasing lead into the environment where it can be inhaled as dust by those who use them, especially children.
"There are a lot of things we don't know," Gerstenberger said. "We were worried about ripping out fields that might create a greater dust hazard than what's there."
The synthetic turf industry is grappling with the issue, said Doyle, whose Atlanta-based trade group represents 158 companies.
"A lot of members for some time have been making turf without pigment that contains lead chromate," Doyle said.
Contact reporter Keith Rogers at krogers @reviewjournal.com or 702-383-0308.